Management of patients on extracorporeal membrane oxygenation (ECMO)
| Venovenous ECMO | Venoarterial ECMO | |
|---|---|---|
| Aim | Oxygenation and carbon dioxide removal | Maintain tissue perfusion |
| ECMO circuit | Adjust sweep gas oxygen fraction and flow rate to maintain ventilation needs | Adjust pump flow to maintain cardiac output needs |
| Mechanical ventilation | Minimize tidal volume and fraction of inspired oxygen (Fio2) to reduce ventilator-induced lung injury (but peripheral capillary oxygen saturation should be kept ≥ 86%) | Maintain lung protective ventilation but adjust FiO2 to ensure upper body oxygenation (especially in patients on peripheral venoarterial ECMO) |
| Anticoagulation | Conservative anticoagulation with target activated partial thromboplastin time 4–60 seconds | Moderate anticoagulation to minimize thrombus formation in oxygenator that would result in distal stroke (target activated partial thromboplastin time 60–80 seconds) |
| Weaninga | Readiness assessment when there is improvement in lung compliance and tidal volumes | Readiness assessment when there is myocardial recovery with improved pulse pressure and contractility on echocardiography |
| Circuit weaning: Maintain on standard ventilator settings (FiO2 ≤ 0.5, positive end-expiratory pressure ≤ 10 cm H2O, airway plateau pressure ≤ 30 cm H2O) and reduce flow rate of sweep gas to ≤ 2 L/minute; wean off if able to maintain adequate respiratory rate and gas exchange in 2–4 hours | Circuit weaning: Reduce pump flow rates in increments of 0.5 L to 2 L/minute over 24–36 hoursb; wean in surgical setting if able to maintain stable mean arterial pressure and central venous pressure and acceptable contractility on echocardiography; may require brief period of inotropic support after weaning | |
| Complications | Patient: Hemorrhage (intracranial and gastrointestinal bleeding are common), infection, renal failure | Patient: Hemorrhage (intracranial and gastrointestinal bleeding are common), infections, renal failure, lower limb ischemia, thromboembolism at cannulation site, harlequin syndrome |
| Mechanical: Inappropriate cannulation leading to insufficient oxygenation, vessel wall injury, thrombus formation within the circuit, pulmonary or systemic thromboembolism or air embolism from circuit | Mechanical: Inappropriate cannulation leading to insufficient oxygenation, vessel wall injury, thrombus formation within the circuit, pulmonary or systemic thromboembolism or air embolism from circuit |